2015 lv mv electrical installation guide by schneiderelectric

Electrical installation guideAccording to IEC international standards

This technical guide is the result of a collective effort. Responsible for the coordination of this edition: Laurent MISCHLER

Edition: 2015

Price: 60

ISBN: 978.2.9531643.3.6 N dpt lgal: 1er semestre 2008

Schneider Electric All rights reserved in all countries

The Electrical Installation Guide is a single document covering the techniques and standards related to low-voltage electrical installations. It is intended for electrical professionals in companies, design offices, inspection organisations, etc.

This Technical Guide is aimed at professional users and is only intended to provide them guidelines for the definition of an industrial, tertiary or domestic electrical installation. Information and guidelines contained in this Guide are provided AS IS. Schneider Electric makes no warranty of any kind, whether express or implied, such as but not limited to the warranties of merchantability and fitness for a particular purpose, nor assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this Guide, nor represents that its use would not infringe privately owned rights. The purpose of this guide is to facilitate the implementation of International installation standards for designers & contractors, but in all cases the original text of International or local standards in force shall prevail.

This new edition has been published to take into account changes in techniques, standards and regulations, in particular electrical installation standard IEC 60364 series.

We thank all the readers of the previous edition of this guide for their comments that have helped improve the current edition. We also thank the many people and organisations, too numerous to name here, who have contributed in one way or another to the preparation of this guide.

This guide has been written for electrical Engineers who have to design, select electrical equipment, install these equipment and, inspect or maintain low-voltage electrical installations in compliance with international Standards of the International Electrotechnical Commission (IEC).Which technical solution will guarantee that all relevant safety rules are met? This question has been a permanent guideline for the elaboration of this document.

An international Standard such as the IEC 60364 series Low voltage Electrical Installations specifies extensively the rules to comply with to ensure safety and correct operational functioning of all types of electrical installations. As the Standard must be extensive, and has to be applicable to all types of equipment and the technical solutions in use worldwide, the text of the IEC rules is complex, and not presented in a ready-to-use order. The Standard cannot therefore be considered as a working handbook, but only as a reference document.

The aim of the present guide is to provide a clear, practical and step-by-step explanation for the complete study of an electrical installation, according to IEC 60364 series and other relevant IEC Standards. The first chapter (A) presents the methodology to be used, and refers to all chapters of the guide according to the different steps of the study.

We all hope that you, the reader, will find this handbook genuinely helpful.

Schneider Electric S.A.

Acknowlegements

This guide has been realized by a team of experienced international experts, on the base of IEC 60364 series of standard, and include the latest developments in electrical standardization.

We shall mention particularly the following experts and their area of expertise:

Chapter

Christian Collombet D, G

Bernard Jover R

Jacques Schonek D, G, L, M, N

Didier Fulchiron B

Jean-Marc Biasse B

Didier Mignardot J, P

Eric Bettega E

Pascal Lepretre E

Emmanuel Genevray E, P

Eric Breuill F

Didier Segura F

Fleur Janet K

Franck Mgret G

Geoffroy De-Labrouhe K

Jean Marc Lupin L, M

Daniel Barstz N

Herv Lambert N, A

Jrome Lecomte H

Matthieu Guillot F, H, P

Jean-Franois Rey F

Schneider Electric - Electrical installation guide 2015

Tools for more efficiencyin electrical installation design

Electrical installation Wiki

The Electrical Installation Guide is also available on-line as a wiki in 4 languages:

> in English electrical-installation.org > in Russian ru.electrical-installation.org > in Chinese cn.electrical-installation.org > in German de.electrical-installation.org

Our experts constantly contribute to its evolution. Industry and academic professionals can collaborate too!

Power Management Blog

In the Schneider Electric blog, you will find the best tips about standards, tools, software, safety and latest technical news shared by our experts. You will find even more information about innovations and business opportunities. This is your place to leave us your comments and to engage discussion about your expertise. You might want to sharewith your Twitter or LinkedIn followers.

> blog.schneider-electric.com/power-management-metering-monitoring-power-quality

English

Russian

Chinese

German

http://electrical-installation.orghttp://ru.electrical-installation.orghttp://cn.electrical-installation.orghttp://de.electrical-installation.orghttp://blog.schneider-electric.com/power-management-metering-monitoring-power-quality/http://www.electrical-installation.org/enwiki/Main_Pagehttp://ru.electrical-installation.org/ruwiki/_http://cn.electrical-installation.org/http://blog.schneider-electric.com/power-management-metering-monitoring-power-quality/http://de.electrical-installation.org


Ecodial Advanced Calculation 4

The new Ecodial Advanced Calculation 4 software is dedicated to electrical installation calculation in accordance with IEC60364 international standard or national standards.

This 4th generation offers new features like: p management of operating mode (parallel transformers, back-up generators) p discrimination analysis associating curves checking and discrimination tables,

direct access to protection settings

Online Electrical calculation Tools

A set of tools designed to help you: p display on one chart the time-current cuves of different circuit-breakers or fuses p check the discrimination between two circuit-breakers or fuses, or two Residual

Current devices (RCD), search all the circuit-breakers or fuses that can be selective/cascading with a defined circuit-breaker or fuse

p calculate the Cross Section Area of cables and build a cable schedule p calculate the voltage drop of a defined cable and check the maximum length

> hto.power.schneider-electric.com

Online tools

http://hto.power.schneider-electric.com/CBT/Apps/index.aspxhttp://hto.power.schneider-electric.com/CBT/Apps/index.aspx

ForewordEtienne TISON, International Electrotechnical Commission (IEC) TC64 Chairman. The task of the IEC Technical Committee 64 is to develop and keep up-to-date requirements - for the protection of persons against electrical shock, and- for the design, verification and implementation of low voltage electrical installations.

Series of standard such as IEC 60364 developed by IEC TC64 is considered by the international community as the basis of the majority of national low-voltage wiring rules.

IEC 60364 series is mainly focussed on safety due the use of electricity by people who may not be aware of risk resulting from the use of electricity.

But modern electrical installations are increasingly complex, due to external input such as- electromagnetic disturbances- energy efficiency- ...

Consequently, designers, installers and consumers need guidance on the selection and installation of electrical equipment.

Schneider Electric has developed this Electrical Installation Guide dedicated to low voltage electrical installations. It is based on IEC TC64 standards such as IEC 60364 series and provides additional information in order to help designers, contractors and controllers for implementing correct low-voltage electrical installations.

As TC64 Chairman, it is my great pleasure and honour to introduce this guide. I am sure it will be used fruitfully by all persons involved in the implementation of all low-voltage electrical installations.

Etienne TISON

Etienne TISON has been working with Schneider Electric since 1978. He has been always involved is various activities in low voltage field.In 2008, Etienne TISON has been appointed Chairman of IEC TC64 as well as Chairman of CENELEC TC64.

Electrical installation guide 2015

General rules of electrical installation design

A

B

C

D

E

F

G

H

J

K

L

M

N

Connection to the MV utility distribution network

Connection to the LV utility distribution network

MV & LV architecture selection guide for buildings

LV Distribution

Protection against electric shocks and electric fires

Sizing and protection of conductors

LV switchgear: functions & selection

Overvoltage protection

Energy efficiency in electrical distribution

Power Factor Correction

Harmonic management

Characteristics of particular sources and loads

PPhotovoltaic installations

QResidential and other special locations

REMC guidelines


General rules of electrical installation design 1 Methodology A2 2 Rules and statutory regulations A5 3 Installed power loads - Characteristics A11 4 Power loading of an installation A17

Connection to the MV utility distribution network 1 Power supply at medium voltage B2 2 Procedure for the establishment of a new substation B10 3 Protection against electrical hazards, faults and miss operations in electrical installations B12 4 The consumer substation with LV metering B23 5 The consumer substation with MV metering B26 6 Choice and use of MV equipment and MV/LV transformer B29

7 Substation including generators and parallel operation of transformers B38

8 Types and constitution of MV/LV distribution substations B41

Connection to the LV utility distribution network 1 Low-voltage utility distribution networks C2 2 Tariffs and metering C16

MV & LV architecture selection guide for buildings 1 Stakes of architecture design D3 2 Simplified architecture design process D4 3 Electrical installation characteristics D7 4 Technological characteristics D11 5 Architecture assessment criteria D12 6 Choice of architecture fundamentals D14 7 Choice of architecture details D18 8 Choice of equiment D25 9 Recommendations for architecture optimization D26 10 Glossary D30 11 Example: electrical installation in a printworks D31

LV Distribution 1 Earthing schemes E2 2 The installation system E15 3 External influences E34

Protection against electric shocks and electric fire 1 General F2 2 Protection against direct contact F4 3 Protection against indirect contact F6 4 Protection of goods due to insulation fault F17 5 Implementation of the TT system F19 6 Implementation of the TN system F23 7 Implementation of the IT system F29 8 Residual current devices RCDs F36 9 Arc Fault Detection Devices (AFDD) F43

Sizing and protection of conductors 1 General G2 2 Practical method for determining the smallest allowable G7 cross-sectional area of circuit conductors 3 Determination of voltage drop G19 4 Short-circuit current G23 5 Particular cases of short-circuit current G29 6 Protective earthing conductor (PE) G36 7 The neutral conductor G41

8 Worked example of cable calculation G45

A

B

CD

E

F

General contents

G


LV switchgear: functions & selection

1 The basic functions of LV switchgear H2 2 The switchgear H5 3 Choice of switchgear H10 4 Circuit breaker H11

5 Maintenance of low voltage switchgear H32

Overvoltage protection 1 Overvoltage of atmospheric origin J2 2 Principle of lightning protection J7 3 Design of the electrical installation protection system J13 4 Installation of SPDs J24 5 Application J28 6 Technical supplements J32

Energy Efficiency in electrical distribution 1 Energy Efficiency in brief K2 2 Energy efficiency and electricity K3 3 Diagnosis through electrical measurement K6 4 Energy saving opportunities K8 5 How to evaluate energy savings K23

Power Factor Correction 1 Power factor and Reactive power L2 2 Why to improve the power factor? L6 3 How to improve the power factor? L8 4 Where to install power correction capacitors? L11 5 How to determine the optimum level of compensation? L13 6 Compensation at the terminals of a transformer L16 7 Power factor correction of induction motors L19 8 Example of an installation before and after power-factor correction L21 9 The effects of harmonics L22 10 Implementation of capacitor banks L26

Harmonic management 1 The problem: why is it necessary to manage harmonics? M2 2 Definition and origin of harmonics M3 3 Essential indicators of harmonic distortion M7 and measurement principles 4 Harmonic measurement in electrical networks M10 5 Main effects of hamronis in electrical installations M13 6 Standards M20 7 Solutions to mitigate harmonics M21

Characteristics of particular sources and loads 1 Protection of a LV generator set and the downstream circuits N2 2 Uninterruptible Power Supply Units (UPS) N11 3 Protection of LV/LV transformers N24 4 Lighting circuits N27 5 Asynchronous motors N55

Photovoltaic installations 1 Benefits of photovoltaic energy P2 2 Background and technology P3 3 PV System and Installation Rules P10 4 PV installation architectures P18 5 Monitoring P31

General contents

J

K

L

M

N

H

P


Residential and other special locations 1 Residential and similar premises Q2 2 Bathrooms and showers Q8

3 Recommendations applicable to special installations and locations Q12 EMC guidelines 1 Electrical distribution R2 2 Earthing principles and structures R3 3 Implementation R5 4 Coupling mechanisms and counter-measures R20 5 Wiring recommendations R26

Q

R

General contents


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Contents Methodology A2

Rules and statutory regulations A5 2.1 Definition of voltage ranges A5 2.2 Regulations A6 2.3 Standards A6 2.4 Quality and safety of an electrical installation A7 2.5 Initial testing of an installation A8 2.6 Put in out of danger the existing electrical installations A8 2.7 Periodic check-testing of an installation A9 2.8 Conformity assessement (with standards and specifications) of equipment used in the installation A9 2.9 Environment A10

Installed power loads - Characteristics A11 3.1 Induction motors A11 3.2 Resistive-type heating appliances and incandescent lamps (conventional or halogen) A13 3.3 Fluorescent lamps A14 3.4 Discharge lamps A15

3.5 LED lamps & fixtures A16

Power loading of an installation A17 4.1 Installed power (kW) A17 4.2 Installed apparent power (kVA) A17 4.3 Estimation of actual maximum kVA demand A18 4.4 Example of application of factors ku and ks A21 4.5 Choice of transformer rating A22 4.6 Choice of power-supply sources A23

Chapter AGeneral rules of electrical installation design

1 2

3

4


A - General rules of electrical installation design

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For the best results in electrical installation design it is recommended to read and to use all the chapters of this guide in the order in which they are presented.

Rules and statutory regulationsRange of low-voltage extends from 0 V to 1000 V in a.c. and from 0 V to 1500 V in d.c. One of the first decision id the selection of type of current between the alternative current which corresponds to the most common type of current through out the world and the direct current. Then designers have to select the most appropriate rated voltage within these ranges of voltages. When connected to a LV public network, the type of current and the rated voltage are already selected and imposed by the Utility.Compliance with national regulations is then the second priority of the designers of electrical installation. Regulations may be based on national or international standards such as the IEC 60364 series.Selection of equipment complying with national or international product standards and appropriate verification of the completed installation is a powerful mean for providing a safe installation with the expected quality. Defining and complying with the verification and testing of the electrical installation at its completion as well as periodic time will guarantee the safety and the quality of this installation all along its life cycle. Conformity of equipment according to the appropriate product standards used within the installation is also of prime importance for the level of safety and quality.Environmental conditions will become more and more stringent and will need to be considered at the design stage of the installation. This may include national or regional regulations considering the material used in the equipment as well as the dismantling of the installation at its end of life.

Installed power loads - CharacteristicsA review of all applications needing to be supplied with electricity is to be done. Any possible extensions or modifications during the whole life of the electrical installation are to be considered. Such a review aimed to estimate the current flowing in each circuit of the installation and the power supplies needed.The total current or power demand can be calculated from the data relative to the location and power of each load, together with the knowledge of the operating modes (steady state demand, starting conditions, non simultaneous operation, etc.)Estimation of the maximum power demand may use various factors depending on the type of application; type of equipment and type of circuits used within the electrical installation.From these data, the power required from the supply source and (where appropriate) the number of sources necessary for an adequate supply to the installation is readily obtained.Local information regarding tariff structures is also required to allow the best choice of connection arrangement to the power-supply network, e.g. at medium voltage or low voltage level.

Connection to the MV public distribution networkWhere this connection is made at the Medium Voltage level a consumer-type substation will have to be studied, built and equipped. This substation may be an outdoor or indoor installation conforming to relevant standards and regulations (the low-voltage section may be studied separately if necessary). Metering at medium-voltage or low-voltage is possible in this case.

Connection to the LV utility distribution networkWhere the connection is made at the Low Voltage level the installation will be connected to the local power network and will (necessarily) be metered according to LV tariffs.

MV & LV architecture selection guideThe whole electrical system including the MV installation and the LV installation is to be studied as a complete system. The customer expectations and technical parameters will impact the architecture of the system as well as the electrical installation characteristics.Determination of the most suitable architecture of the MV/LV main distribution and LV power distribution level is often the result of optimization and compromise.Neutral earthing arrangements are chosen according to local regulations, constraints related to the power-supply, and to the type of loads.

1 Methodology


A3 - Installed power loads - CharacteristicsA4 - Power loading of an installation

B - Connection to the MV utility distribution network

C - Connection to the LV utility distribution network

D - MV & LV architecture selection guide


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The distribution equipment (panelboards, switchgears, circuit connections, ...) are determined from building plans and from the location and grouping of loads.The type of premises and allocation can influence their immunity to externaldisturbances.

LV distributionThe system earthing is one protective measures commonly used for the protection against electric shocks. These systems earthings have a major impact on the LV electrical installation architecture and they need to be analysed as early as possible. Advantages and drawbacks are to be analysed for a correct selection.Another aspect needing to be considered at the earlier stage is the external influences. In large electrical installation, different external influences may be encountered and need to be considered independently. As a result of these external influences proper selection of equipment according to their IP or IK codes has to be made.

Protection against electric shocksProtection against electric shock consists in providing provision for basic protection (protection against direct contact) with provision for fault protection (protection against indirect contact). Coordinated provisions result in a protective measure.One of the most common protective measures consists in automatic disconnection of supply where the provision for fault protection consists in the implementation of a system earthing. Deep understanding of each standardized system (TT, TN and IT system) is necessary for a correct implementation.

Sizing and protection of conductorsSelection of cross-sectional-areas of cables or isolated conductors for line conductors is certainly one of the most important tasks of the designing process of an electrical installation as this greatly influences the selection of overcurrent protective devices, the voltage drop along these conductors and the estimation of the prospective short-circuits currents: the maximum value relates to the overcurrent protection and the minimum value relates to the fault protection by automatic disconnection of supply. This has to be done for each circuit of the installation.Similar task is to be done for the neutral conductors and for the Protective Earth (PE) conductor.

LV switchgear: functions & selectionOnce the short-circuit current are estimated, protective devices can be selected for the overcurrent protection. Circuit breakers have also other possible functions such as switching and isolation. A complete understanding of the functionalities offered by all switchgear and controlgear within the installation is necessary. Correct selection of all devices can now be done. A comprehensive understanding of all functionalities offered by the circuit breakers is of prime importance as this is the device offering the largest variety of functions.

Overvoltage protectionDirect or indirect lightning strokes can damage electrical equipment at a distance of several kilometres. Operating voltage surges, transient and industrial frequency over-voltage can also produce the same consequences. All protective measures against overvoltage need to be assessed. One of the most used corresponds to the use of Surge Protective Devices (SPD). Their selection; installation and protection within the electrical installation request some particular attention.

Energy efficiency in electrical distributionImplementation of active energy efficiency measures within the electrical installation can produce high benefits for the user or owner: reduced power consumption, reduced cost of energy, better use of electrical equipment. These measures will most of the time request specific design for the installation as measuring electricity consumption either per application (lighting, heating, process) or per area (floor, workshop) present particular interest for reducing the electricity consumption still keeping the same level of service provided to the user.

Reactive energyThe power factor correction within electrical installations is carried out locally, globally or as a combination of both methods. Improving the power factor has a direct impact on the billing of consumed electricity and may also have an impact on the energy efiiciency.

J - Overvoltage protection

L - Power Factor Correction

1 Methodology

F - Protection against electric shocks

G - Sizing and protection of conductors

H - LV switchgear: functions & selection

E - LV Distribution

K Energy efficiency in electrical distribution



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HarmonicsHarmonic currents in the network affect the quality of energy and are at the origin of many disturbances as overloads, vibrations, ageing of equipment, trouble of sensitive equipment, of local area networks, telephone networks. This chapter deals with the origins and the effects of harmonics and explain how to measure them and present the solutions.

Particular supply sources and loadsParticular items or equipment are studied:b Specific sources such as alternators or invertersb Specific loads with special characteristics, such as induction motors, lighting circuits or LV/LV transformersb Specific systems, such as direct-current networks.

A green and economical energyThe solar energy development has to respect specific installation rules.

Generic applicationsCertain premises and locations are subject to particularly strict regulations: the most common example being residential dwellings.

EMC GuidelinesSome basic rules must be followed in order to ensure Electromagnetic Compatibility. Non observance of these rules may have serious consequences in the operation of the electrical installation: disturbance of communication systems, nuisance tripping of protection devices, and even destruction of sensitive devices.

Ecodial softwareEcodial software(1) provides a complete design package for LV installations, in accordance with IEC standards and recommendations.

The following features are included:b Construction of one-line diagramsb Calculation of short-circuit currents according to several operating modes (normal, back-up, load shedding)b Calculation of voltage dropsb Optimization of cable sizesb Required ratings and settings of switchgear and fusegearb Discrimination of protective devicesb Optimization of switchgear using cascading b Verification of the protection of people and circuitsb Comprehensive print-out of the foregoing calculated design data

There is a number of tools which can help to speed-up the design process. As an example, to choose a combination of components to protect and control an asynchronous motor, with proper coordination (type 1, 2 or total, as defined in international standard IEC 60947-4-1), rather than selecting this combination using paper tables, it is much faster to use tools such as the Low Voltage Motor Starter Solution Guide.

(1) Ecodial is a Schneider Electric software available in several languages and according to different electrical installation standards.

1 Methodology

N - Characteristics of particular sources and loads

P - Photovoltaic Installations

M - Harmonic management

Q - Residential and other special locations

R - EMC guidelines

A companion tool of the Electrical Installation Guide

http://www.schneider-electric.com/products/ww/en/5100-software/5110-electrical-design-software/61013-ecodial-advanced-calculationhttp://www.schneider-electric.com/products/ww/en/5100-software/5110-electrical-design-software/61210-lv-motor-starter-solution-guide-v34/http://www.schneider-electric.com/products/ww/en/5100-software/5110-electrical-design-software/61210-lv-motor-starter-solution-guide-v34/


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Low-voltage installations are usually governed by a number of regulatory and advisory texts, which may be classified as follows:b Statutory regulations (decrees, factory acts, etc.)b Codes of practice, regulations issued by professional institutions, job specificationsb National and international standards for installationsb National and international standards for products

2.1 Definition of voltage rangesIEC voltage standards and recommendations

2 Rules and statutory regulations

Three-phase four-wire or three-wire systems Single-phase three-wire systems Nominal voltage (V) Nominal voltage (V) 50 Hz 60 Hz 60 Hz 120/208 120/240(d)

230(c) 240(c) 230/400(a) 230/400(c) 277/480(a)

480 347/600 600400/690(b) 1000 600

(a) The value of 230/400 V is the result of the evolution of 220/380 V and 240/415 V systems which has been completed in Europe and many other countries. However, 220/380 V and 240/415 V systems still exist.(b) The value of 400/690 V is the result of the evolution of 380/660 V systems which has been completed in Europe and many other countries. However, 380/660 V systems still exist.(c) The value of 200 V or 220 V is also used in some countries.(d) The values of 100/200 V are also used in some countries on 50 Hz or 60 Hz systems.

Fig. A1: Standard voltages between 100 V and 1000 V (IEC 60038 Edition 7.0 2009-06)

Fig. A2: AC 3 phases Standard voltages above 1 kV and not exceeding 35 kV (IEC 60038 Edition 7.0 2009)(a)

Series I Series II Highest voltage Nominal system Highest voltage Nominal systemfor equipment (kV) voltage (kV) for equipment (kV) voltage (kV)3.6(b) 3.3(b) 3(b) 4.40(b) 4.16(b)

7.2(b) 6.6(b) 6(b) 12 11 10 13.2(c) 12.47(c)

13.97(c) 13.2(c)

14.52(b) 13.8(b)

(17.5) (15) 24 22 20 26.4(c, e) 24.94(c, e)

36(d) 33(d) 30(d) 36.5(2) 34.5(c)

40.5(d) 35(d)

Note 1: It is recommended that in any one country the ratio between two adjacent nominal voltages should be not less than two.Note 2: In a normal system of Series I, the highest voltage and the lowest voltage do not differ by more than approximately 10 % from the nominal voltage of the system. In a normal system of Series II, the highest voltage does not differ by more than +5 % and the lowest voltage by more than -10 % from the nominal voltage of the system.(a) These systems are generally three-wire systems, unless otherwise indicated. The values indicated are voltages between phases.The values indicated in parentheses should be considered as non-preferred values. It is recommended that these values should not be used for new systems to be constructed in future.(b) These values should not be used for new public distribution systems.(c) These systems are generally four-wire systems and the values indicated are voltages between phases. The voltage to neutral is equal to the indicated value divided by 1.73.(d) The unification of these values is under consideration.(e) The values of 22.9 kV for nominal voltage and 24.2 kV or 25.8 kV for highest voltage for equipment are also used in some countries.



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2.2 RegulationsIn most countries, electrical installations shall comply with more than one set of regulations, issued by National Authorities or by recognized private bodies. It is essential to take into account these local constraints before starting the design.These regulations may be based on national standards derived from the IEC 60364: Low-voltage electrical installations.

2.3 StandardsThis Guide is based on relevant IEC standards, in particular IEC 60364. IEC 60364 has been established by engineering experts of all countries in the world comparing their experience at an international level. Currently, the safety principles of IEC 60364 series, IEC 61140, 60479 series and IEC 61201 are the fundamentals of most electrical standards in the world (see table below and next page).

IEC 60038 IEC standard voltagesIEC 60076-2 Power transformers - Temperature rise for liquid immersed transformersIEC 60076-3 Power transformers - Insulation levels, dielectric tests and external clearances in airIEC 60076-5 Power transformers - Ability to withstand short-circuitIEC 60076-10 Power transformers - Determination of sound levelsIEC 60146-1-1 Semiconductor converters - General requirements and line commutated converters - Specifications of basic requirementsIEC 60255-1 Measuring relays and protection equipment - Common requirementsIEC 60269-1 Low-voltage fuses - General requirementsIEC 60269-2 Low-voltage fuses - Supplementary requirements for fuses for use by authorized persons (fuses mainly for industrial application) - Examples

of standardized systems of fuses A to KIEC 60282-1 High-voltage fuses - Current-limiting fusesIEC 60287-1-1 Electric cables - Calculation of the current rating - Current rating equations (100 % load factor) and calculation of losses - GeneralIEC 60364-1 Low-voltage electrical installations - Fundamental principles, assessment of general characteristics, definitionsIEC 60364-4-41 Low-voltage electrical installations - Protection for safety - Protection against electric shockIEC 60364-4-42 Low-voltage electrical installations - Protection for safety - Protection against thermal effectsIEC 60364-4-43 Low-voltage electrical installations - Protection for safety - Protection against overcurrentIEC 60364-4-44 Low-voltage electrical installations - Protection for safety - Protection against voltage disturbances and electromagnetic disturbancesIEC 60364-5-51 Low-voltage electrical installations - Selection and erection of electrical equipment - Common rulesIEC 60364-5-52 Low-voltage electrical installations - Selection and erection of electrical equipment - Wiring systemsIEC 60364-5-53 Low-voltage electrical installations - Selection and erection of electrical equipment - Isolation, switching and controlIEC 60364-5-54 Low-voltage electrical installations - Selection and erection of electrical equipment - Earthing arrangements and protective conductorsIEC 60364-5-55 Low-voltage electrical installations - Selection and erection of electrical equipment - Other equipmentIEC 60364-6 Low-voltage electrical installations - VerificationIEC 60364-7-701 Low-voltage electrical installations - Requirements for special installations or locations - Locations containing a bath or showerIEC 60364-7-702 Low-voltage electrical installations - Requirements for special installations or locations - Swimming pools and fountainsIEC 60364-7-703 Low-voltage electrical installations - Requirements for special installations or locations - Rooms and cabins containing sauna heatersIEC 60364-7-704 Low-voltage electrical installations - Requirements for special installations or locations - Construction and demolition site installationsIEC 60364-7-705 Low-voltage electrical installations - Requirements for special installations or locations - Agricultural and horticultural premisesIEC 60364-7-706 Low-voltage electrical installations - Requirements for special installations or locations - Conducting locations with restrictive movementIEC 60364-7-708 Low-voltage electrical installations - Requirements for special installations or locations - Caravan parks, camping parks and similar locationsIEC 60364-7-709 Low-voltage electrical installations - Requirements for special installations or locations - Marinas and similar locationsIEC 60364-7-710 Low-voltage electrical installations - Requirements for special installations or locations - Medical locationsIEC 60364-7-711 Low-voltage electrical installations - Requirements for special installations or locations - Exhibitions, shows and standsIEC 60364-7-712 Low-voltage electrical installations - Requirements for special installations or locations - Solar photovoltaic (PV) power supply systemsIEC 60364-7-713 Low-voltage electrical installations - Requirements for special installations or locations - FurnitureIEC 60364-7-714 Low-voltage electrical installations - Requirements for special installations or locations - External lighting installationsIEC 60364-7-715 Low-voltage electrical installations - Requirements for special installations or locations - Extra-low-voltage lighting installationsIEC 60364-7-717 Low-voltage electrical installations - Requirements for special installations or locations - Mobile or transportable unitsIEC 60364-7-718 Low-voltage electrical installations - Requirements for special installations or locations - Communal facilities and workplacesIEC 60364-7-721 Low-voltage electrical installations - Requirements for special installations or locations - Electrical installations in caravans and motor caravansIEC 60364-7-729 Low-voltage electrical installations - Requirements for special installations or locations - Operating or maintenance gangwaysIEC 60364-7-740 Low-voltage electrical installations - Requirements for special installations or locations - Temporary electrical installations for structures,

amusement devices and booths at fairgrounds, amusement parks and circusesIEC 60364-7-753 Low-voltage electrical installations - Requirements for special installations or locations - Heating cables and embedded heating systemsIEC 60364-8-1 Low-voltage electrical installations - Energy efficiencyIEC 60446 Basic and safety principles for man-machine interface, marking and identification - Identification of equipment terminals, conductors

terminations and conductorsIEC 60479-1 Effects of current on human beings and livestock - General aspectsIEC 60479-2 Effects of current on human beings and livestock - Special aspectsIEC 60479-3 Effects of current on human beings and livestock - Effects of currents passing through the body of livestockIEC 60529 Degrees of protection provided by enclosures (IP code)IEC 60644 Specification for high-voltage fuse-links for motor circuit applications

(Continued on next page)


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IEC 60664 Insulation coordination for equipment within low-voltage systems - all partsIEC 60715 Dimensions of low-voltage switchgear and controlgear. Standardized mounting on rails for mechanical support of electrical devices in switchgear

and controlgear installations.IEC 60724 Short-circuit temperature limits of electric cables with rated voltages of 1 kV (Um = 1.2 kV) and 3 kV (Um = 3.6 kV)IEC 60755 General requirements for residual current operated protective devicesIEC 60787 Application guide for the selection of high-voltage current-limiting fuses-link for transformer circuitIEC 60831-1 Shunt power capacitors of the self-healing type for a.c. systems having a rated voltage up to and including 1000 V - Part 1: General - Performance,

testing and rating - Safety requirements - Guide for installation and operationIEC 60831-2 Shunt power capacitors of the self-healing type for a.c. systems having a rated voltage up to and including 1000 V - Part 2: Ageing test, self-healing

test and destruction testIEC 60947-1 Low-voltage switchgear and controlgear - General rulesIEC 60947-2 Low-voltage switchgear and controlgear - Circuit breakersIEC 60947-3 Low-voltage switchgear and controlgear - Switches, disconnectors, switch-disconnectors and fuse-combination unitsIEC 60947-4-1 Low-voltage switchgear and controlgear - Contactors and motor-starters - Electromechanical contactors and motor-startersIEC 60947-6-1 Low-voltage switchgear and controlgear - Multiple function equipment - Transfer switching equipmentIEC 61000 series Electromagnetic compatibility (EMC)IEC 61140 Protection against electric shocks - common aspects for installation and equipmentIEC 61201 Use of conventional touch voltage limits - Application guideIEC/TR 61439-0 Low-voltage switchgear and controlgear assemblies - Guidance to specifying assembliesIEC 61439-1 Low-voltage switchgear and controlgear assemblies - General rulesIEC 61439-2 Low-voltage switchgear and controlgear assemblies - Power switchgear and controlgear assembliesIEC 61439-3 Low-voltage switchgear and controlgear assemblies - Distribution boards intended to be operated by ordinary persons (DBO)IEC 61439-4 Low-voltage switchgear and controlgear assemblies - Particular requirements for assemblies for construction sites (ACS)IEC 61439-5 Low-voltage switchgear and controlgear assemblies - Assemblies for power distribution in public networksIEC 61439-6 Low-voltage switchgear and controlgear assemblies - Busbar trunking systems (busways)IEC 61557-1 Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. - Equipment for testing, measuring or monitoring of protective

measures - General requirementsIEC 61557-8 Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. - Equipment for testing, measuring or monitoring of protective

measures - Insulation monitoring devices for IT systemsIEC 61557-9 Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. - Equipment for testing, measuring or monitoring of protective

measures - Equipment for insulation fault location in IT systemsIEC 61557-12 Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. - Equipment for testing, measuring or monitoring of protective

measures - Performance measuring and monitoring devices (PMD)IEC 61558-2-6 Safety of transformers, reactors, power supply units and similar products for supply voltages up to 1100 V - Particular requirements and test

for safety isolating transformers and power supply units incorporating isolating transformersIEC 61643-11 Low-voltage surge protective devices - Surge protective devices connected to low-voltage power systems - Requirements and test methodsIEC 61643-12 Low-voltage surge protective devices - Surge protective devices connected to low-voltage power distribution systems - Selection and application

principlesIEC 61643-21 Low voltage surge protective devices - Surge protective devices connected to telecommunications and signalling networks - Performance

requirements and testing methodsIEC 61643-22 Low-voltage surge protective devices - Surge protective devices connected to telecommunications and signalling networks - Selection and application principlesIEC 61921 Power capacitors - Low-voltage power factor correction banksIEC 62271-1 High-voltage switchgear and controlgear - Common specificationsIEC 62271-100 High-voltage switchgear and controlgear - Alternating-current circuit breakersIEC 62271-101 High-voltage switchgear and controlgear - Synthetic testingIEC 62271-102 High-voltage switchgear and controlgear - Alternating current disconnectors and earthing switchesIEC 62271-103 High-voltage switchgear and controlgear - Switches for rated voltages above 1 kV up to and including 52 kVIEC 62271-105 High-voltage switchgear and controlgear - Alternating current switch-fuse combinations for rated voltages above 1 kV up to and including 52 kVIEC 62271-200 High-voltage switchgear and controlgear - Alternating current metal-enclosed switchgear and controlgear for rated voltages above 1 kV

and up to and including 52 kVIEC 62271-202 High-voltage switchgear and controlgear - High-voltage/low voltage prefabricated substationsIEC 62305-1 Protection against lightning - Part 1: General principlesIEC 62305-2 Protection against lightning - Part 2: Risk managementIEC 62305-3 Protection against lightning - Part 3: Physical damage to structures and life hazardIEC 62305-4 Protection against lightning - Part 4: Electrical and electronic systems within structures

(Concluded)

2.4 Quality and safety of an electrical installationIn so far as control procedures are respected, quality and safety will be assured only if:b The design has been done according to the latest edition of the appropriate wiring rulesb The electrical equipment comply with relevant product standardsb The initial checking of conformity of the electrical installation with the standard and regulation has been achievedb The periodic checking of the installation recommended is respected.




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2.5 Initial testing of an installationBefore a utility will connect an installation to its supply network, strict pre-commissioning electrical tests and visual inspections by the authority, or by its appointed agent, must be satisfied.

These tests are made according to local (governmental and/or institutional) regulations, which may differ slightly from one country to another. The principles of all such regulations however, are common, and are based on the observance of rigorous safety rules in the design and realization of the installation.

IEC 60364-6 and related standards included in this guide are based on an international consensus for such tests, intended to cover all the safety measures and approved installation practices normally required for residential, commercial and (the majority of) industrial buildings. Many industries however have additional regulations related to a particular product (petroleum, coal, natural gas, etc.). Such additional requirements are beyond the scope of this guide.

The pre-commissioning electrical tests and visual-inspection checks for installations in buildings include, typically, all of the following:b Electrical continuity and conductivity tests of protective, equipotential and earth-bonding conductorsb Insulation resistance tests between live conductors and the protective conductors connected to the earthing arrangementb Test of compliance of SELV and PELV circuits or for electrical separationb Insulation resistance/impedance of floors and wallsb Protection by automatic disconnection of the supplyv For TN, by measurement of the fault loop impedance, and by verification of the characteristics and/or the effectiveness of the associated protective devices (overcurrent protective device and RCD)v For TT, by measurement of the resistance RA of the earth electrode of the exposed-conductive-parts, and by verification of the characteristics and/or the effectiveness of the associated protective devices (overcurrent protective device and RCD)v For IT, by calculation or measurement of the current Id in case of a fist fault at the line conductor or at the neutral, and with the test done for TN system where conditions are similar to TN system in case of a double insulation fault situation, with the test done for TT system where the conditions are similar to TT system in case of a double insulation fault situation.b Additional protection by verifying the effectiveness of the protective measureb Polarity test where the rules prohibit the installation of single pole switching devices in the neutral conductor.b Check of phase sequence in case of multiphase circuitb Functional test of switchgear and controlgear by verifying their installation and adjustment b Voltage drop by measuring the circuit impedance or by using diagrams

These tests and checks are basic (but not exhaustive) to the majority of installations, while numerous other tests and rules are included in the regulations to cover particular cases, for example: installations based on class 2 insulation, special locations, etc.The aim of this guide is to draw attention to the particular features of different types of installation, and to indicate the essential rules to be observed in order to achieve a satisfactory level of quality, which will ensure safe and trouble-free performance. The methods recommended in this guide, modified if necessary to comply with any possible variation imposed by a utility, are intended to satisfy all precommissioning test and inspection requirements.After verification and testing an initial report must be provided including records of inspection, records of circuits tested together with the test result and possible repairs or improvements of the installation.

2.6 Put in out of danger the existing electrical installationsThis subject is in real progress cause of the statistics with origin electrical installation (number of old and recognised dangerous electrical installations, existing installations not in adequation with the future needs etc.)


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2.7 Periodic check-testing of an installationIn many countries, all industrial and commercial-building installations, together with installations in buildings used for public gatherings, must be re-tested periodically by authorized agents.The following tests should be performedb Verification of RCD effectiveness and adjustmentsb Appropriate measurements for providing safety of persons against effects of electric shock and protection against damage to property against fire and heatb Confirmation that the installation is not damagedb Identification of installation defectsFigure A3 shows the frequency of testing commonly prescribed according to the kind of installation concerned.

Conformity of equipment with the relevant standards can be attested in several ways

Fig A3: Frequency of check-tests commonly recommended for an electrical installation

As for the initial verification, a reporting of periodic verification is to be provided.

2.8 Conformity assessement (with standards and specifications) of equipment used in the installationThe conformity assessement of equipment with the relevant standards can be attested:b By mark of conformity granted by the certification body concerned, orb By a certificate of conformity issued by a certification body, orb By a declaration of conformity given by the manufacturer.

Declaration of conformityAs business, the declaration of conformity, including the technical documentation, is generally used in for high voltage equipments or for specific products. In Europe, the CE declaration is a mandatory declaration of conformity.Note: CE markingIn Europe, the European directives require the manufacturer or his authorized representative to affix the CE marking on his own responsibility. It means that:b The product meets the legal requirementsb It is presumed to be marketable in Europe.The CE marking is neither a mark of origin nor a mark of conformity, it completes the declaration of conformity and the technical documents of the equipments.

Certificate of conformityA certificate of conformity can reinforce the manufacturer's declaration and the customer's confidence. It could be requested by the regulation of the countries, imposed by the customers (Marine, Nuclear,..), be mandatory to garanty the maintenance or the consistency between the equipments.

Mark of conformityMarks of conformity are strong strategic tools to validate a durable conformity. It consolidates the confidence with the brand of the manufacturer. A mark of

Type of installation Testing frequencyInstallations b Locations at which a risk of degradation, Annually which require fire or explosion exists the protection b Temporary installations at worksites of employees b Locations at which MV installations exist b Restrictive conducting locations where mobile equipment is used Other cases Every 3 yearsInstallations in buildings According to the type of establishment From one to used for public gatherings, and its capacity for receiving the public three years where protection against the risks of fire and panic are required Residential According to local regulations Example : the REBT in Belgium which imposes a periodic control each 20 years.




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conformity is delivered by certification body if the equipment meets the requirements from an applicable referential (including the standard) and after verification of the manufacturers quality management system.Audit on the production and follow up on the equipments are made globally each year.

Quality assuranceA laboratory for testing samples cannot certify the conformity of an entire production run: these tests are called type tests. In some tests for conformity to standards, the samples are destroyed (tests on fuses, for example).Only the manufacturer can certify that the fabricated products have, in fact, the characteristics stated.Quality assurance certification is intended to complete the initial declaration or certification of conformity.As proof that all the necessary measures have been taken for assuring the quality of production, the manufacturer obtains certification of the quality control system which monitors the fabrication of the product concerned. These certificates are issued by organizations specializing in quality control, and are based on the international standard ISO 9001: 2000.

These standards define three model systems of quality assurance control corresponding to different situations rather than to different levels of quality:

b Model 3 defines assurance of quality by inspection and checking of final products

b Model 2 includes, in addition to checking of the final product, verification of the manufacturing process. For example, this method is applied, to the manufacturer of fuses where performance characteristics cannot be checked without destroying the fuse

b Model 1 corresponds to model 2, but with the additional requirement that the quality of the design process must be rigorously scrutinized; for example, where it is not intended to fabricate and test a prototype (case of a custom-built product made to specification).

2.9 EnvironmentThe contribution of the whole electrical installation to sustainable development can be significantly improved through the design of the installation. Actually, it has been shown that an optimised design of the installation, taking into account operation conditions, MV/LV substations location and distribution structure (switchboards, busways, cables), can reduce substantially environmental impacts (raw material depletion, energy depletion, end of life), especially in term of energy efficiency. Beside its architecture, environmental specification of the electrical component and equipment is a fundamental step for an eco-friendly installation. In particular to ensure proper environmental information and anticipate regulation. In Europe several Directives concerning electrical equipments have been published, leading the worldwide move to more environment safe products. a) RoHS Directive (Restriction of Hazardous Substances): in force since July 2006 and revised on 2012. It aims to eliminate from products six hazardous substances: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE) from most of end user electrical products.. Though electrical installations being large scale fixed installation are not in the scope, RoHS compliance requirement may be a recommendation for a sustainable installation b) WEEE Directive (Waste of Electrical and Electronic Equipment): in force since August 2005 and currently under revision. Its purpose is to improve the end of life treatments for household and non household equipment, under the responsibility of the manufacturers. As for RoHS, electrical installations are not in the scope of this directive. However, End of Life Product information is recommended to optimise recycling process and cost. c) Energy Related Product, also called Ecodesign. Apart for some equipments like lighting or motors for which implementing measures are compulsory, there are no legal requirements that directly apply to installation. However, trend is to provide electrical equipments with their Environmental Product Declarattion, as it is becoming for Construction Products, to anticipate Building Market coming requirements. d) REACh: (Registration Evaluation Authorisation of Chemicals). In force since 2009, it aims to control chemical use and restrict application when necessary to reduce hazards to people and environment. With regards to EE and installations, it implies any supplier shall, upon request, communicate to its customer the hazardous substances content in its product (so called SVHC). Then, an installer should ensure that its suppliers have the appropriate information availableIn other parts of the world new legislations will follow the same objectives.


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3 Installed power loads - Characteristics

The examination of actual values of apparent-power required by each load enables the establishment of:

b A declared power demand which determines the contract for the supply of energy

b The rating of the MV/LV transformer, where applicable (allowing for expected increased load)

b Levels of load current at each distribution board.

3.1 Induction motorsCurrent demandThe full-load current Ia supplied to the motor is given by the following formulae:

b 3-phase motor: Ia = Pn x 1000 / (3 x U x x cos )b 1-phase motor: Ia = Pn x 1000 / (U x x cos )where

Ia: current demand (in amps)Pn: nominal power (in kW)

U: voltage between phases for 3-phase motors and voltage between the terminals for single-phase motors (in volts). A single-phase motor may be connected phase-to-neutral or phase-to-phase.

: per-unit efficiency, i.e. output kW / input kWcos : power factor, i.e. kW input / kVA input.

Subtransient current and protection settingb Subtransient current peak value can be very high; typical value is about 12 to 15 times the rms rated value Inm. Sometimes this value can reach 25 times Inm.

b Schneider Electric circuit breakers, contactors and thermal relays are designed to withstand motor starts with very high subtransient current (subtransient peak value can be up to 19 times the rms rated value Inm).

b If unexpected tripping of the overcurrent protection occurs during starting, this means the starting current exceeds the normal limits. As a result, some maximum switchgear withstands can be reached, life time can be reduced and even some devices can be destroyed. In order to avoid such a situation, oversizing of the switchgear must be considered.

b Schneider Electric switchgears are designed to ensure the protection of motor starters against short-circuits. According to the risk, tables show the combination of circuit breaker, contactor and thermal relay to obtain type 1 or type 2 coordination (see chapter N).

Motor starting currentAlthough high efficiency motors can be found on the market, in practice their starting currents are roughly the same as some of standard motors.

The use of start-delta starter, static soft start unit or variable speed drive allows to reduce the value of the starting current (Example: 4 Ia instead of 7.5 Ia).

Compensation of reactive-power (kvar) supplied to induction motorsIt is generally advantageous for technical and financial reasons to reduce the current supplied to induction motors. This can be achieved by using capacitors without affecting the power output of the motors.The application of this principle to the operation of induction motors is generally referred to as power-factor improvement or power-factor correction.

As discussed in chapter L, the apparent power (kVA) supplied to an induction motor can be significantly reduced by the use of shunt-connected capacitors. Reduction of input kVA means a corresponding reduction of input current (since the voltage remains constant).

Compensation of reactive-power is particularly advised for motors that operate for long periods at reduced power.

As noted above


B10 B - General design - Regulations -Installed power 3 Installed power loads -

Characteristics

The examination of actual values of apparent-power required by each load enablesthe establishment of:

c A declared power demand which determines the contract for the supply of energyc The rating of the HV/LV transformer, where applicable (allowing for expectedincreases load)

c Levels of load current at each distribution board

3.1 Induction motors

Current demandThe full-load current Ia supplied to the motor is given by the following formulae:

c 3-phase motor: Ia = Pn x 1,000 / 3 x U x x cos c 1-phase motor: Ia = Pn x 1,000 / U x x cos where

Ia: current demand (in amps)Pn: nominal power (in kW of active power)U: voltage between phases for 3-phase motors and voltage between the terminalsfor single-phase motors (in volts). A single-phase motor may be connected phase-to-neutral or phase-to-phase.

: per-unit efficiency, i.e. output kW / input kWcos : power factor, i.e. kW input / kVA input

Subtransient current and protection settingc Subtransient current peak value can be very high ; typical value is about 12to 15 times the RMS rated value Inm. Sometimes this value can reach 25 times Inm.c Merlin Gerin circuit breakers, Telemecanique contactors and thermal relays aredesigned to withstand motor starts with very high subtransient current (subtransientpeak value can be up to 19 RMS rated value Inm).c If unexpected tripping of the overcurrent protection occurs during starting, thismeans the starting current exceeds the normal limits. As a result, some maximumswitchgears withstands can be reach, life time can be reduce and even somedevices can be destroyed. In order to avoid such a situation, oversizing of theswitchgear must be considered.

c Merlin Gerin and Telemecanique switchgears are designed to ensure theprotection of motor starters against short circuits. According to the risk, tables showthe combination of circuit breaker, contactor and thermal relay to obtain type 1 ortype 2 coordination (see chapter M).

Motor starting currentAlthough high efficiency motors can be find on the market, in practice their startingcurrents are roughly the same as some of standard motors.

The use of start-delta starter, static soft start unit or speed drive converter allows toreduce the value of the starting current (Example : 4 Ia instead of 7.5 Ia).

Compensation of reactive-power (kvar) supplied to induction motorsIt is generally advantageous for technical and financial reasons to reduce the currentsupplied to induction motors. This can be achieved by using capacitors withoutaffecting the power output of the motors.The application of this principle to the operation of induction motors is generallyreferred to as power-factor improvement or power-factor correction.

As discussed in chapter K, the apparent power (kVA) supplied to an induction motorcan be significantly reduced by the use of shunt-connected capacitors. Reduction ofinput kVA means a corresponding reduction of input current (since the voltageremains constant).

Compensation of reactive-power is particularly advised for motors that operate forlong periods at reduced power.

As noted above cos = kW inputkVA input

so that a kVA input reduction in kVA input will

increase (i.e. improve) the value of cos .

An examination of the actual apparent-powerdemands of different loads: a necessarypreliminary step in the design of aLV installation

The nominal power in kW (Pn) of a motorindicates its rated equivalent mechanical poweroutput.The apparent power in kVA (Pa) supplied to themotor is a function of the output, the motorefficiency and the power factor.Pa = Pn / cos

so that a kVA input reduction will increase

(i.e. improve) the value of cos .

An examination of the actual apparent-power demands of different loads: a necessary preliminary step in the design of a LV installation

The nominal power in kW (Pn) of a motor indicates its rated equivalent mechanical power output.The apparent power in kVA (Pa) supplied to the motor is a function of the output, the motor efficiency and the power factor.

Pa =Pncos



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The current supplied to the motor, after power-factor correction, is given by:

B11


B - General design - Regulations -Installed power

The current supplied to the motor, after power-factor correction, is given by:

I cos cos '

=

where cos is the power factor before compensation and cos is the power factorafter compensation, Ia being the original current.It should be noted that speed drive converter provides reactive energy compensation.Figure B4 below shows, in function of motor rated power, standard motor currentvalues for several voltage supplies.

3 Installed power loads -Characteristics

kW hp 230 V 380 - 400 V 440 - 500 V 690 V415 V 480 V

A A A A A A0.18 - 1.0 - 0.6 - 0.48 0.350.25 - 1.5 - 0.85 - 0.68 0.490.37 - 1.9 - 1.1 - 0.88 0.64- 1/2 - 1.3 - 1.1 - -0.55 - 2.6 - 1.5 - 1.2 0.87- 3/4 - 1.8 - 1.6 - -- 1 - 2.3 - 2.1 - -0.75 - 3.3 - 1.9 - 1.5 1.11.1 - 4.7 - 2.7 - 2.2 1.6- 1-1/2 - 3.3 - 3.0 - -- 2 - 4.3 - 3.4 - -1.5 - 6.3 - 3.6 - 2.9 2.12.2 - 8.5 - 4.9 - 3.9 2.8- 3 - 6.1 - 4.8 - -3.0 - 11.3 - 6.5 - 5.2 3.83.7 - - - - - - -4 - 15 9.7 8.5 7.6 6.8 4.95.5 - 20 - 11.5 - 9.2 6.7- 7-1/2 - 14.0 - 11.0 - -- 10 - 18.0 - 14.0 - -7.5 - 27 - 15.5 - 12.4 8.911 - 38.0 - 22.0 - 17.6 12.8- 15 - 27.0 - 21.0 - -- 20 - 34.0 - 27.0 - -15 - 51 - 29 - 23 1718.5 - 61 - 35 - 28 21- 25 - 44 - 34 -22 - 72 - 41 - 33 24- 30 - 51 - 40 - -- 40 - 66 - 52 - -30 - 96 - 55 - 44 3237 - 115 - 66 - 53 39- 50 - 83 - 65 - -- 60 - 103 - 77 - -45 - 140 - 80 - 64 4755 - 169 - 97 - 78 57- 75 - 128 - 96 - -- 100 - 165 - 124 - -75 - 230 - 132 - 106 7790 - 278 - 160 - 128 93- 125 - 208 - 156 - -110 - 340 - 195 156 113- 150 - 240 - 180 - -132 - 400 - 230 - 184 134- 200 - 320 - 240 - -150 - - - - - - -160 - 487 - 280 - 224 162185 - - - - - - -- 250 - 403 - 302 - -200 - 609 - 350 - 280 203220 - - - - - - -- 300 - 482 - 361 - -250 - 748 - 430 - 344 250280 - - - - - - -- 350 - 560 - 414 - -- 400 - 636 - 474 - -300 - - - - - - -

Fig. B4 : Rated operational power and currents (continued on next page)

Ia

where cos is the power factor before compensation and cos is the power factor after compensation, Ia being the original current.

Figure A4 below shows, in function of motor rated power, standard motor current values for several voltage supplies.

kW hp 230 V 380 - 400 V 440 - 500 V 690 V 415 V 480 V A A A A A A0.18 - 1.0 - 0.6 - 0.48 0.35 0.25 - 1.5 - 0.85 - 0.68 0.49 0.37 - 1.9 - 1.1 - 0.88 0.64- 1/2 - 1.3 - 1.1 - - 0.55 - 2.6 - 1.5 - 1.2 0.87 - 3/4 - 1.8 - 1.6 - -- 1 - 2.3 - 2.1 - - 0.75 - 3.3 - 1.9 - 1.5 1.1 1.1 - 4.7 - 2.7 - 2.2 1.6- 1-1/2 - 3.3 - 3.0 - - - 2 - 4.3 - 3.4 - - 1.5 - 6.3 - 3.6 - 2.9 2.12.2 - 8.5 - 4.9 - 3.9 2.8 - 3 - 6.1 - 4.8 - - 3.0 - 11.3 - 6.5 - 5.2 3.83.7 - - - - - - - 4 - 15 9.7 8.5 7.6 6.8 4.9 5.5 - 20 - 11.5 - 9.2 6.7- 7-1/2 - 14.0 - 11.0 - - - 10 - 18.0 - 14.0 - - 7.5 - 27 - 15.5 - 12.4 8.911 - 38.0 - 22.0 - 17.6 12.8 - 15 - 27.0 - 21.0 - - - 20 - 34.0 - 27.0 - -15 - 51 - 29 - 23 17 18.5 - 61 - 35 - 28 21 - 25 - 44 - 34 -22 - 72 - 41 - 33 24 - 30 - 51 - 40 - - - 40 - 66 - 52 - -30 - 96 - 55 - 44 32 37 - 115 - 66 - 53 39 - 50 - 83 - 65 - -- 60 - 103 - 77 - - 45 - 140 - 80 - 64 47 55 - 169 - 97 - 78 57- 75 - 128 - 96 - - - 100 - 165 - 124 - - 75 - 230 - 132 - 106 7790 - 278 - 160 - 128 93 - 125 - 208 - 156 - - 110 - 340 - 195 156 113- 150 - 240 - 180 - - 132 - 400 - 230 - 184 134 - 200 - 320 - 240 - -150 - - - - - - - 160 - 487 - 280 - 224 162 185 - - - - - - -- 250 - 403 - 302 - - 200 - 609 - 350 - 280 203 220 - - - - - - -- 300 - 482 - 361 - - 250 - 748 - 430 - 344 250 280 - - - - - - -- 350 - 560 - 414 - - - 400 - 636 - 474 - - 300 - - - - - - -

Fig. A4: Rated operational power and currents (continued on next page)


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kW hp 230 V 380 - 400 V 440 - 500 V 690 V 415 V 480 V A A A A A A315 - 940 - 540 - 432 313 - 540 - - - 515 - - 335 - - - - - - -355 - 1061 - 610 - 488 354 - 500 - 786 - 590 - - 375 - - - - - - -400 - 1200 - 690 - 552 400 425 - - - - - - - 450 - - - - - - -475 - - - - - - - 500 - 1478 - 850 - 680 493 530 - - - - - - -560 - 1652 - 950 - 760 551 600 - - - - - - - 630 - 1844 - 1060 - 848 615670 - - - - - - - 710 - 2070 - 1190 - 952 690 750 - - - - - - -800 - 2340 - 1346 - 1076 780 850 - - - - - - - 900 - 2640 - 1518 - 1214 880950 - - - - - - - 1000 - 2910 - 1673 - 1339 970

Fig. A4: Rated operational power and currents (concluded)

3.2 Resistive-type heating appliances and incandescent lamps (conventional or halogen)The current demand of a heating appliance or an incandescent lamp is easily obtained from the nominal power Pn quoted by the manufacturer (i.e. cos = 1) (see Fig. A5).

Fig. A5: Current demands of resistive heating and incandescent lighting (conventional or halogen) appliances

Nominal Current demand (A)power 1-phase 1-phase 3-phase 3-phase (kW) 127 V 230 V 230 V 400 V0.1 0.79 0.43 0.25 0.140.2 1.58 0.87 0.50 0.290.5 3.94 2.17 1.26 0.721 7.9 4.35 2.51 1.441.5 11.8 6.52 3.77 2.172 15.8 8.70 5.02 2.892.5 19.7 10.9 6.28 3.613 23.6 13 7.53 4.333.5 27.6 15.2 8.72 5.054 31.5 17.4 10 5.774.5 35.4 19.6 11.3 6.55 39.4 21.7 12.6 7.226 47.2 26.1 15.1 8.667 55.1 30.4 17.6 10.18 63 34.8 20.1 11.59 71 39.1 22.6 1310 79 43.5 25.1 14.4




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(2) Power-factor correction is often referred to as compensation in discharge-lighting-tube terminology. Cos is approximately 0.95 (the zero values of V and I are almost in phase) but the power factor is 0.5 due to the impulsive form of the current, the peak of which occurs late in each half cycle

The currents are given by:

b 3-phase case: Ia = PnU3

(1)

Ia =PnU

(1)

b 1-phase case:

Ia =Pn

U3

(1)

Ia =PnU

(1)

where U is the voltage between the terminals of the equipment.

For an incandescent lamp, the use of halogen gas allows a more concentrated light source. The light output is increased and the lifetime of the lamp is doubled.

Note: At the instant of switching on, the cold filament gives rise to a very brief but intense peak of current.

3.3 Fluorescent lamps

Fluorescent lamps and related equipmentThe power Pn (watts) indicated on the tube of a fluorescent lamp does not include the power dissipated in the ballast.

The current is given by:

B13


B - General design - Regulations -Installed power 3 Installed power loads -

Characteristics

(1) Power-factor correction is often referred to ascompensation in discharge-lighting-tube terminology.Cos is approximately 0.95 (the zero values of V and I arealmost in phase) but the power factor is 0.5 due to theimpulsive form of the current, the peak of which occurs latein each half cycle

Fig. B6 : Current demands and power consumption of commonly-dimensioned fluorescentlighting tubes (at 230 V-50 Hz)

c 1-phase case: Ia = PnU

(1)


The current demand of a heating appliance or an incandescent lamp is easilyobtained from the nominal power Pn quoted by the manufacturer (i.e. cos = 1).

The currents are given by:

c 3-phase case: Ia

=Pn

U3

(1)

c 1-phase case: Ia = PnU

(1)


For an incandescent lamp, the use of halogen gas allows a more concentrated lightsource. The light output is increased and the lifetime of the lamp is doubled.

Note: At the instant of switching on, the cold filament gives rise to a very brief butintense peak of current.

Fluorescent lamps and related equipmentThe power Pn (watts) indicated on the tube of a fluorescent lamp does not includethe power dissipated in the ballast.

The current is given by:

Ia cos

=+P Pn

Uballast

If no power-loss value is indicated for the ballast, a figure of 25% of Pn may be used.

Standard tubular fluorescent lampsThe power Pn (watts) indicated on the tube of a fluorescent lamp does not include thepower dissipated in the ballast.

The current taken by the complete circuit is given by:

Ia cos

=+P Pn

Uballast

where U = the voltage applied to the lamp, complete with its related equipment.With (unless otherwise indicated):c cos = 0.6 with no power factor (PF) correction(1) capacitorc cos = 0.86 with PF correction(1) (single or twin tubes)c cos = 0.96 for electronic ballast.If no power-loss value is indicated for the ballast, a figure of 25% of Pn may be used.Figure B6 gives these values for different arrangements of ballast.

Arrangement Tube power Current (A) at 230 V Tubeof lamps, starters (W) (2) Magnetic ballast Electronic lengthand ballasts ballast (cm)

Without PF With PFcorrection correctioncapacitor capacitor

Single tube 18 0.20 0.14 0.10 6036 0.33 0.23 0.18 12058 0.50 0.36 0.28 150

Twin tubes 2 x 18 0.28 0.18 602 x 36 0.46 0.35 1202 x 58 0.72 0.52 150

(2) Power in watts marked on tube

Compact fluorescent lampsCompact fluorescent lamps have the same characteristics of economy and long lifeas classical tubes. They are commonly used in public places which are permanentlyilluminated (for example: corridors, hallways, bars, etc.) and can be mounted insituations otherwise illuminated by incandescent lamps (see Fig. B7 next page).

Where U = the voltage applied to the lamp, complete with its related equipment.If no power-loss value is indicated for the ballast, a figure of 25 % of Pn may be used.

Standard tubular fluorescent lampsWith (unless otherwise indicated):b cos = 0.6 with no power factor (PF) correction(2) capacitorb cos = 0.86 with PF correction(2) (single or twin tubes)b cos = 0.96 for electronic ballast.If no power-loss value is indicated for the ballast, a figure of 25 % of Pn may be used.Figure A6 gives these values for different arrangements of ballast.

(1) Ia in amps; U in volts. Pn is in watts. If Pn is in kW, then multiply the equation by 1000

Fig. A6: Current demands and power consumption of commonly-dimensioned fluorescent lighting tubes (at 230 V-50 Hz)

Arrangement Tube power Current (A) at 230 V Tubeof lamps, starters (W) (3) Magnetic ballast Electronic length and ballasts ballast (cm) Without PF With PF correction correction capacitor capacitorSingle tube 18 0.20 0.14 0.10 60 36 0.33 0.23 0.18 120 58 0.50 0.36 0.28 150Twin tubes 2 x 18 0.28 0.18 60 2 x 36 0.46 0.35 120 2 x 58 0.72 0.52 150(3) Power in watts marked on tube

Compact fluorescent lampsCompact fluorescent lamps have the same characteristics of economy and long life as classical tubes. They are commonly used in public places which are permanently illuminated (for example: corridors, hallways, bars, etc.) and can be mounted in situations otherwise illuminated by incandescent lamps (see Fig. A7 next page).


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The power in watts indicated on the tube of a discharge lamp does not include the power dissipated in the ballast.

Fig. A7: Current demands and power consumption of compact fluorescent lamps (at 230 V-50 Hz)

Type of lamp Lamp power Current at 230 V (W) (A)Separated 10 0.080 ballast lamp 18 0.110 26 0.150 Integrated 8 0.075 ballast lamp 11 0.095 16 0.125 21 0.170

Fig. A8a: Current demands of discharge lamps

Type of Power Current In(A) Starting Luminous Average Utilizationlamp (W) demand PF not PF Ia/In Period efficiency timelife of (W) at corrected corrected (mins) (lumens lamp (h) 230 V 400 V 230 V 400 V 230 V 400 V per watt)

High-pressure sodium vapour lamps50 60 0.76 0.3 1.4 to 1.6 4 to 6 80 to 120 9000 b Lighting of70 80 1 0.45 large halls100 115 1.2 0.65 b Outdoor spaces150 168 1.8 0.85 b Public lighting250 274 3 1.4 400 431 4.4 2.2 1000 1055 10.45 4.9 Low-pressure sodium vapour lamps 26 34.5 0.45 0.17 1.1 to 1.3 7 to 15 100 to 200 8000 b Lighting of 36 46.5 0.22 to 12000 autoroutes66 80.5 0.39 b Security lighting,91 105.5 0.49 station 131 154 0.69 b Platform, storage areasMercury vapour + metal halide (also called metal-iodide) 70 80.5 1 0.40 1.7 3 to 5 70 to 90 6000 b Lighting of very150 172 1.80 0.88 6000 large areas by250 276 2.10 1.35 6000 projectors (for400 425 3.40 2.15 6000 example: sports 1000 1046 8.25 5.30 6000 stadiums, etc.) 2000 2092 2052 16.50 8.60 10.50 6 2000 Mercury vapour + fluorescent substance (fluorescent bulb) 50 57 0.6 0.30 1.7 to 2 3 to 6 40 to 60 8000 b Workshops80 90 0.8 0.45 to 12000 with very high125 141 1.15 0.70 ceilings (halls,250 268 2.15 1.35 hangars)400 421 3.25 2.15 b Outdoor lighting700 731 5.4 3.85 b Low light output(1)

1000 1046 8.25 5.30 2000 2140 2080 15 11 6.1 (1) Replaced by sodium vapour lamps.Note: these lamps are sensitive to voltage dips. They extinguish if the voltage falls to less than 50 % of their nominal voltage, and will not re-ignite before cooling for approximately 4 minutes.Note: Sodium vapour low-pressure lamps have a light-output efficiency which is superior to that of all other sources. However, use of these lamps is restricted by the fact that the yellow-orange colour emitted makes colour recognition practically impossible.

3.4 Discharge lamps

Figure A8a gives the current taken by a complete unit, including all associated ancillary equipment.

These lamps depend on the luminous electrical discharge through a gas or vapour of a metallic compound, which is contained in a hermetically-sealed transparent envelope at a pre-determined pressure. These lamps have a long start-up time, during which the current Ia is greater than the nominal current In. Power and current demands are given for different types of lamp (typical average values which may differ slightly from one manufacturer to another).



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3.5 LED lamps & fixturesA lamp or luminaire with LED technology is powered by a driver: b can be integrated into the bulb (tube or lamp for retrofit) : in this case refer to the power indicated on the lampb if separated : in that case it is necessary to take into account the power dissipated in the driver and the power indicated for one or several associated LED modules.

This technology has a very short start-up time. On the other hand, the inrush current at the powering is generally very higher than for fluorescent lamp with electronic ballast.

Note: The power in Watts indicated on the LED module with a separated driver doesnt include the power dissipated in the driver.

Fig. A8b: Main characteristics of LED lamps & fixtures

Power Power Starting Luminous Average Utilizationdemand factor Inrush Inrush Full efficiency timelife (W) at current current Time (lumens 230 V Ip/In time to per watt) (microsec) start

3 to 400 W > 0.9 Up to 250 < 250 < 0.5 100 to 140 20000 b All lighting microsec to 1 sec to 50000 applications in all domains (housing, commercial and industrial building, infrastructure)


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In order to design an installation, the actual maximum load demand likely to be imposed on the power-supply system must be assessed.

To base the design simply on the arithmetic sum of all the loads existing in the installation would be extravagantly uneconomical, and bad engineering practice.

The aim of this chapter is to show how some factors taking into account the diversity (non simultaneous operation of all appliances of a given group) and utilization (e.g. an electric motor is not generally operated at its full-load capability, etc.) of all existing and projected loads can be assessed. The values given are based on experience and on records taken from actual installations. In addition to providing basic installation-design data on individual circuits, the results will provide a global value for the installation, from which the requirements of a supply system (distribution network, MV/LV transformer, or generating set) can be specified.

4.1 Installed power (kW)

The installed power is the sum of the nominal powers of all power consuming devices in the installation.This is not the power to be actually supplied in practice.

Most electrical appliances and equipments are marked to indicate their nominal power rating (Pn).The installed power is the sum of the nominal powers of all power-consuming devices in the installation. This is not the power to be actually supplied in practice. This is the case for electric motors, where the power rating refers to the output power at its driving shaft. The input power consumption will evidently be greater.

Fluorescent and discharge lamps associated with stabilizing ballasts, are other cases in which the nominal power indicated on the lamp is less than the power consumed by the lamp and its ballast.

Methods of assessing the actual power consumption of motors and lighting appliances are given in Section 3 of this Chapter.

The power demand (kW) is necessary to choose the rated power of a generating set or battery, and where the requirements of a prime mover have to be considered.

For a power supply from a LV public-supply network, or through a MV/LV transformer, the significant quantity is the apparent power in kVA.

4 Power loading of an installation

4.2 Installed apparent power (kVA)The installed apparent power is commonly assumed to be the arithmetical sum of the kVA of individual loads. The maximum estimated kVA to be supplied however is not equal to the total installed kVA.

The apparent-power demand of a load (which might be a single appliance) is obtained from its nominal power rating (corrected if necessary, as noted above for motors, etc.) and the application of the following coefficients:

= the per-unit efficiency = output kW / input kWcos = the power factor = kW / kVAThe apparent-power kVA demand of the loadPa = Pn /( x cos )From this value, the full-load current Ia (A)(1) taken by the load will be:

b

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B - General design - Regulations -Installed power

In order to design an installation, the actual maximum load demand likely to beimposed on the power-supply system must be assessed.

To base the design simply on the arithmetic sum of all the loads existing in theinstallation would be extravagantly uneconomical, and bad engineering practice.

The aim of this chapter is to show how some factors taking into account the diversity(nonsimultaneous operation of all appliances of a given group) and utilization (e.g.an electric motor is not generally operated at its full-load capability, etc.) of allexisting and projected loads can be assessed. The values given are based onexperience and on records taken from actual installations. In addition to providingbasic installation-design data on individual circuits, the results will provide a globalvalue for the installation, from which the requirements of a supply system(distribution network, HV/LV transformer, or generating set) can be specified.

4.1 Installed power (kW)

The installed power is the sum of the nominalpowers of all powerconsuming devices in theinstallation.This is not the power to be actually supplied inpractice.

Most electrical appliances and equipments are marked to indicate their nominalpower rating (Pn).The installed power is the sum of the nominal powers of all power-consumingdevices in the installation. This is not the power to be actually supplied in practice.This is the case for electric motors, where the power rating refers to the outputpower at its driving shaft. The input power consumption will evidently be greater

Fluorescent and discharge lamps associated with stabilizing ballasts, are othercases in which the nominal power indicated on the lamp is less than the powerconsumed by the lamp and its ballast.

Methods of assessing the actual power consumption of motors and lightingappliances are given in Section 3 of this Chapter.

The power demand (kW) is necessary to choose the rated power of a generating setor battery, and where the requirements of a prime mover have to be considered.

For a power supply from a LV public-supply network, or through a HV/LV transformer,the significant quantity is the apparent power in kVA.

4.2 Installed apparent power (kVA)

The installed apparent power is commonly assumed to be the arithmetical sum ofthe kVA of individual loads. The maximum estimated kVA to be supplied however isnot equal to the total installed kVA.

The apparent-power demand of a load (which might be a single appliance) isobtained from its nominal power rating (corrected if necessary, as noted above formotors, etc.) and the application of the following coefficients:

= the per-unit efficiency = output kW / input kWcos = the power factor = kW / kVA

The apparent-power kVA demand of the loadPa = Pn /( x cos )

From this value, the full-load current Ia (A)(1) taken by the load will be:

c Ia = Pa x 10V

3

for single phase-to-neutral connected load

c Ia = Pa x 103 x U

3

for three-phase balanced load where:V = phase-to-neutral voltage (volts)U = phase-to-phase voltage (volts)It may be noted that, strictly sp

2015 lv mv electrical installation guide by schneiderelectric

Engineering

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